Anthrax Signs and Symptoms

Cutaneous anthrax occurs one to seven days (usually two to five) after spores enter the body through breaks in the skin.

This form most commonly affects the exposed areas of the arms and, to a lesser extent, the head and neck.

The infection may spread throughout the body in up to 20% of untreated cases.

Cutaneous anthrax begins as a small pimple-like lesion (a sore) that enlarges in 24-48 hours to form a "malignant pustule" at the site of the infection. This sore (about 2-3 cm or about an inch) is round with a raised edge. The sore is not painful. The central area of infection is surrounded by small blisters filled with bloody or clear fluid containing many bacteria. A black scab forms at the site of the sore in seven to 10 days and lasts for seven to 14 days before separating. The surrounding area may be swollen and painful and may last long after the scab forms.

Sores that affect the neck may cause swelling that could affect breathing.

Inhalational anthrax

Inhalational anthrax begins abruptly, one to 60 days (usually one to three days) after inhaling large amounts of anthrax spores. The size of the spores is extremely important when it comes to causing disease, and this depends upon the techniques of the person producing the spores. Spores that are too small are inhaled but then immediately exhaled and do not remain in the lungs to cause disease. Spores that are too large do not remain suspended in the air when released and drop to the ground and are thus never inhaled in the first place. Optimal sized spores for an anthrax biological weapon measure 1-5 micrograms in diameter.

A person may initially have no specific respiratory or breathing symptoms but might have a low-grade fever, sore throat, and a nonproductive cough. An exposed person may feel chest pain early in the illness and improve temporarily before rapidly progressing to having severe breathing problems.

Inhalational anthrax progresses rapidly with high fever, severe shortness of breath, rapid breathing, bluish color to the skin, a great deal of sweating, vomiting blood, and chest pain that may be so severe as to seem like a heart attack.

Inhalational anthrax usually causes death when the poisonous toxins produced by the bacteria overwhelm the body systems.

Intestinal anthrax

Swallowing spores may cause intestinal anthrax two to five days later.

People with intestinal anthrax may have nausea, vomiting (also vomit blood), tiredness, no appetite, abdominal pain, and bloody diarrhea, plus a fever.

Intestinal anthrax is difficult to recognize. Shock and death may occur two to five days after it begins.

Oropharyngeal (mouth and throat) anthrax

Swallowing of spores may result in anthrax appearing in the mouth and throat two to seven days after exposure.

People with this type of anthrax may have a sore throat on one side or difficulty swallowing.

Death may occur because the person's throat may swell and cause difficulty breathing.

Septicemic (bloodstream) anthrax

Septicemic anthrax refers to an overwhelming blood infection by anthrax. This can be a complication of inhalational anthrax.

Internal organs may become darkly colored with widespread bleeding. The bacteria multiply in the blood and overwhelm the white blood cells.

Most cases of septicemic anthrax occur following inhalational anthrax. The number of organisms released from the liver or spleen into the bloodstream overwhelms the body's defenses and leads to the production of massive amounts of lethal toxin that result in shock and death.

Anthrax meningitis

This type of anthrax may complicate any form of anthrax and spread throughout the lining tissues of the central nervous system and to the brain.